Railway traffic controlling apparatus



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RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Jan. Q 1955 5 Sheets-Sheet 3 C Figl.v @daag/@MM IDS MDSMMM i r I I l Ig? I i127 I 15g l l l Bbf L F156 121 E 2p-m A 119 19 5225 5D C 1MP 5MP INM/Is IRWS B E @VWS ggws f Il IMP 3MP B1 5MP f F1425' Y nl] H59 INVENT OR Figl, l Earl M.All@n I `By' J,

HIS ATTORNEY Patented June 30, 1936 ilhli'l'ED STATS PATENT OFFICE RAILWAY TRAFFIC CONTROLLING APPARATUS Application January 9, 1935, Serial No. 1,007

Claims.

My invention relates to railway traiiic controlling apparatus, and more particularly to electrically interlocked apparatus for governing or controlling the signals and switches of a track lay- 5 out having ,a plurality of traffic routes.

One object of my invention is to eliminate the usual electro-mechanical locking of the control levers by which the dispatcher or operator controls the switches and signals, by providing a syslO tem of relays having interconnected circuits and controlled by levers in the dispatchers office which are free to be operated at any time. A particular feature of my invention resides in the provision of means whereby a signal lever may be operated to clear a signal for a route at the same time the switch control levers are operated to set up the route, and the signal will be prevented from clearing until each switch of the route governed by the signal agrees as to position with its 204 switch control means. Another object of my invention resides in the provision of means for preventing interference with any signal which is at clear, by the operation of the switch control means for any switch of its route or by the opery ation of the signal control means for an opposing or conflicting signal. Other objects and features of my invention will appear as the description proceeds.

I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.

Referring to the accompanying drawings, Fig. l illustrates diagrammatically the switches and signals of a typical track layout which the apparatus of my invention is adapted to control. Figs. 2 to l2, inclusive, when taken together, constitute a diagrammatic View of one form of the apparatus of my invention arranged for governing the switches and signals of the track layout of Fig. l.

j Similar reference characters refer to similar parts in each of the several views.

Referring to Fig. l, while a specific track layout is disclosed, it is to be understood that the apparatus of my invention is adapted to control other track layouts that may involve entirely different combinations of switches and signals, the relatively simple layout shown, however, being adequate to illustrate the principles of my invention. Fig. l illustrates by a single line diagram each of the two main tracks of a double track railway connected by a crossover comprising the switches I and IA, the upper track being also connected to a siding by a single switch 3. The movement of tralc over the switches is governed by the sig- 5 nals bearing the references 2 and 4 with distinguishing prefixes R and L indicating the direction of traffic governed by the signals. It is to be understood that the rails of the tracks are divided into sections by insulated joints, the main track sections including the switches, and extending 5 from one of a pair of opposing signals to the other, being indicated by the references IT and 3T, respectively, while the adjoining approach sections are indicated by the references 2T, AZT, 4T and A4T, respectively. Each section is provided with l0 the usual closed track circuit including a normally energized track relay in accordance with standard practice, as indicated diagrammatically in the drawings, each track relay being identified by the reference letter R with a prex indicating 15 the track section. The switch sections IT and 3T also each have a slow pickup slow release relay TZ associated therewith.

In order to simplify the drawings and to enable the circuits to be more readily traced, I have iden- 2O tiiied each relay contact by a number and each relay by a letter with distinguishing pref-lx or sufx including a number identifying the switch or signal with which the relay is associated, those contacts not adjacent the respective relays which 25A operate them bearing the reference characters for the respective relays as well as numbers identifying the contacts. Furthermore, instead of showing the source of current for energizing the relays and the wires leading thereto in detail, 30 I have shown only the terminals of the source, which I have designated by the reference character B, referring to the positive or supply terminal, and by the reference character C, referring to the negative or common terminal. Thus, referring 35 to Fig. 2, the circuit for relay ITZ may be traced from one terminal B of the source of current, front contact 5 of track relay ITR, relay ITZ to the other terminal C of the same source, this circuit being opened when relay ITR is shunted due 40 to the occupancy of section IT by a train.

Each of the switches I, IA ,and 3 is actuated by a power operated switch machine of the dual selector type identified in Fig. l by the references ISM, IASM and 35M, respectively. Each switch 45 machine is provided with a motor having an operating circuit controlled by contacts of a polarized relay WR. and similar to the motor circuit for switch I shown in Fig. 3. These polarized switch control relays are shown in Fig. 4, and are 50 controlled by the track relays TR and their repeaters TZ for the switch sections, by the approach locking relays M shown in Fig. 6 and by the manually governed switch control relays NWS and. RWS of Fig, 11, polarized relay 3WR for 55 switch 3 being also controlled by the section locking relay 3S of Fig. 7. Each switch machine provided with the usual circuit controller, which may, for example, be of the type disclosed the Zabel Patents Nos. 1,293,290 and 1,=i13,820,

for controlling those contacts identified in the drawings by the reference SM, such as the motor cut-out contacts of Fig. 3, and the indication contacts for controliing the switch indication relays erating motor, normal polar Contact 8.0i relay IWR, cont-act switch machine ISM,.fleld I4 of the vmotor to the other terminal C of the source, the circuit being opened bycontact I3 when the switch moves to its normal position. The reverse operating circuit is similar butV includes the reverse polar contacts 8 and 'I of relay IWR and contact l5 of ISM which opens when the switch moves its reverse position.

Referring to Fig. 4, the normal energizing circuit for relays iWR and IAWR mayk be traced from terminal B, front cont-act IS of switch controlrelay INWS,"con`tacts II, I3, m29, 2h22 of the various approach locking and track relays as Vindicated on the drawings, relays lil/'R and IAWR in multiple, contacts 23 and 24er' relays ITZ and 3TZ, back ContactY 25 of relay IRWS to terminal C. The reverse energizingr circuit Afor relays IWR and lAWR is similar but includes front contact 25 of relay IRWS and back'contact'l of relay INWS.

Relay SWR is similarly controlled by contacts 2B and 2'I of the switch control relays'SNWS and SRWS, as is obvious from the drawings. It will be clear from the foregoing that the circuits for each of the relays WR are so arranged that the relay will not respon-d to an operation of one of its control relays NWS or RWS unless conditions are favorable for the operation ofthe switch. Y

`Each switch machine is provide-d with a dual selector leverwhich maybe movedeither to a motor position to couple the switch operating mechanism to the' motorof the switch machine to condition the switch for power operation, or to a hand-throw position to uncouple the motor and to vcondition the switch for hand operation by the train crew. When in the handthrow position, the dual selector lever opens the contacts DS of Fig. 1l to deenergize the switch control relays NWS and RWS to maintain the motor circuits open untilrthe dual selector lever is restore-d and one of the switch controi relays is reenergize-d by the dispatcher or operator, and also opens the `contacts DS of Fig. 5

Vto deenergize the indication relay KR andV to thereby' open the sign-al circuits, as hereinafter described, while the switch is conditioned for hand operation.

Referring to Fig. 5, the normal energizing cir"` cuit for'the polarized indication relay IKR may be traced from terminalfB, contacts 23 and 29 controlled by the dual selectorlevers lDS and lADS of switch machines l SM and IASM, contacts 3l) and 3l of the circuit controllers for switch machines IASM and HSM, relay lKR, contacts 32 and 33 to terminal C. The reverse energizing circuit for relay IKRAmay be traced I3 of the circuit controller ofV Ylaterlt No. 1,959,072;

from terminal B, contacts 28, 29, 34, 32, relay IKR, contacts 3l and 35 to terminal C. The cirS cuits for relay SKR are similar but include the dual selector and indication contacts of switch machine 38M only, as is obvons from the drawings. It is to be understood that each indication relay KR will be energized in a position corre= sponding to that of the switch only when `the switch points are closed and locked by the switch machine,'and in thecase of the crossover, when both switches l and IA occupy corresponding positions.

Each indication relay KR has a pair of repeating relays NKP and RKP also shown in Fig.V 5, each relay NKP or RKP being energized by an obvious circuit including contacts such as 3Eand 3l closed when the corresponding relay KR is energized in its normal or `reverse direction, re-V spectively. These repeating relays provide addi# tionai indication contacts for controlling the approach locking relay circuits of Fig. 6 and the signai relay circuits of Fig. 9 as hereinafter described, andV together with the switch control relays ilWS and RWS controlrthe relays INKZ,`

crossover.V Relay 3KZ is energized over aY cir` cuit from terminal B, contacts 38 and 39,'relayV 3KZ to terminal C when switch 3 is'normal and the normal control rel-ayj3NW S is energized, or over the circuit from terminal B,.contac`ts and` 4I, relay 3KZ to terminai C whenV switch 3 is reversed and relay 3RWS is'energized. Relay` INKZ is energized over avcircuit from terminal B, contacts 42, 43, relay INKZ to terminal'C, when switches I and IA are normal and relay INWS is energized, while relay IRKZ is energized over a similar circuit including contacts 44 and 45 when switches I and IA are reversed and relay IRWS is energized. Y

Referring now to Fig. 6, an approach locking relay M is provided for each direction for each main track, the circuitsof these relays being generally similar to those disclosed in the Wallace Relay R2M for example, is normally energized when signal R2 indicates stop by a circuit which Amay be traced from terimin-al B, back contacts 46 and 4l or" the signal relays RAI-I and RBZH, front contact 48 Yand winding of relay RZM to terminal C. If one of these signal relays is energized to clear the corresponding signal, relay RZM is released. Ii'the signal is then put to stop manually, relay REM will pick up over theV circuit including contacts '46 and 4l and front Contact 49 of relay AZER provided there is no train approaching signal R2 and approach section AZT is unoccupied. In the event the approach section is` occupied, however, putting the signal to Vstop will Ycomplete a circuit from terminai B, back contacts 45, 4l', 48, front contact 5B of relay ITR, time element relay ZTE to termin-al C. Relay TE will become energized and after a predeterminedtime interval will close contact to pick up relay R't/I.Y If signal R2 put to stop automatically by theV passage of a train and switchvl is normal, re'- lays ITR, iTZ and ZTR will become released rsA circuit including back contact 52 of relay 2TR, back contact 53 oi reverse indication relay IRKP, and back contact 54 of relay ITZ. If signal R2 is put to stop automatically by the passage of a train and switch I is reversed so that relay IRKP is energized, relays ITR, ITZ, @TR and STZ will become released and relay RZM will be picked up when the train enters section 3T by the circuit including back contact 55 or relay STZ, front contact 53 of relay IRKP and back contact 54 of relay lTZ.

The circuit for the remaining approach locking relays L2M, REM and L4M are generally similar and may be readily traced from the drawings. It will be noted, however, that the approach release circuit for relay L4M includes a front contact 55 of indication relay BNKP which is open when switch 3 is reversed so that when signal LC4 is put to stop manually the release of the locking is eifected only by operation of the time element relay ATE, there being no approach track circuit for the siding.

From a consideration of the circuits of Figs. 4 and 6, it will be clear that the switches I and IA of the cross-over are approach locked when a signal has been cleared for a train approaching from either direction on either main track or on the siding by one ofthe relays M and that the switches are locked by the release of the track relays R when the train accepting the signal occupies section IT or 3T, and that switch 3 is similarly locked by the relays M and R of the upper track only. Switch 3 is however also locked by the release of relay R2M or of ITR when the crossover is reversed, by means of the section locking relay 3S.

Referring to- Fig. 7, a circuit may be traced from terminal B, front contact 5l of relay RQM, front contact 58 and winding of relay 3S to terminal C, which circuit opens to release relay 3S when relay R2M is released by the clearing of arm'b of signal R2 for a movement over the crossover reversed and over switch 3. When a train accepts this signal, relay RZM becomes energized but relay 3S does not pick up as long as the train occupies section IT by reason of contact 5B of relay ITR which is included in the circuit of relay 5S in multiple with contact 58. When the crossover is normal, contact 5S of relay INKP shunts contact 5'I and maintains relay 3S energized independently of relay REM. The control ei'ected by relay 5S is thus such that switch 3 is locked not only when the crossover is reversed and arm b of signal R2 has been cleared, but also if a train passing that signal occupies either section IT or 3T, while if `a signal is cleared for a train moving in the opposite direction over switch 3, relay 3S remains energized and the locking is released as soon as the train leaves section 3T.

The signals shown in Fig. l may be of any suitable type and in practice those signals governing high speed routes will generally be threeposition signals governed in accordance with the condition of other signals in advance, not shown herein, in addition to being subject to manual and track circuit control. To illustrate the present invention, however, it is deemed sufficient to assume merely that each signal indicates proceed or clear when energized and indicates stop when deenergized, A signal relay H is provided for each signal arm, and each signal relay H controls a lighting circuit for the signal as well as the lockingcircuit for the switches in the routes governed by the signal as above described.

Referring to Fig. 8, the diagram at the left ,shows the lighting circuits for the high speed signal represented by arm a of signal R2 by means of which a green lamp G is lighted when signal relay RAZH is energized and front contact IBI is closed, and by which a red lamp R is lighted when the signal relay is deenergized, these circuits being obvious from the drawings.

The lighting circuits for arm a of signal R4 are similar but are controlled by relay LAflH. The diagram at the right of Fig. 8 shows the lighting circuits for the slow speed signal L2 controlled by signal relay LZH and differ from the one described only in that a yellow lamp Y is lighted when the signal relay is energized. The remaining signals are also slow speed signals and have lighting circuits similar to those for signal L2.

The signal relays H are controlled over the signal relay network of Fig. 9, the circuit for each signal relay H being controlled by front contacts of a route relay HX for the corresponding signal and by a back Contact of a route relay HX for an opposing signal. The signal relay network is a counterpart of the track layout and includes a circuit for each direction for each route through the layout, each circuit being formed by conductors corresponding to portions of the track which are connected together by indication contacts controlled in accordance with the positions of the track switches. The route circuit for each signal includes a front contact of the approach locking relay M associated with the opposing signal, thereby not only insuring that a signal can not be cleared unless the opposing signal indicates stop, but also interposing a time delay in the reversal oi the direction of traflic when a signal is put to stop in the face of an approaching train,

Assuming that switches I and IA are normal and sections IT and 2T unoccupied, ii relay R2HX is picked up and relay LZ1-IX is released, relay RAEH will be energized over the circuit from terrninal B, contact 5I of relay LIM, back contact 62 of relay LBHX, contacts 63, Gil, 65, 65, 61, relay RARE, contact 68 to terminal C. Ii relay LZ1-IX is picked up and relay R21-IX is released, relay LZ1-I will be energized independently of track conditions over the circuit from terminal B, contact 65 of relay R2M, contacts ed, 63, front contact G2, relay LZH, contact 'ZB to terminal C.

When switches I and IA are normal, relay LQHX or R51-IX may be picked up at the same time as relay LZHX or R21-IX. If relay L4HX is picked up and relay Ril-IX is released, and sections 3T and 5T are unoccupied and switches i, IA and 3 are normal, relay LAlH will be energized over the circuit from terminal B, contact Ii of relay RM, contacts 12 to i9, inclusive, relay LAQH, contact SEB to terminal C, whiie if switch 3 is reversed, relay LCG-H will be energized independently of track conditions over the circuit from terminal B, contact 'il of relay RSM, contacts 'I2 to '55, inclusive, contact 8i of relay SRKP, relay LCQH, contact BG to terminal C. Likewise, if relay R41-IX. is picked up and relay LQHX is released, relay R4H will be energized independently of track conditions provided switch 3 is locked either normal or reverse over the circuit from terminal B, contact 82 of relay LlM, contacts 15, i4, i3, 12, relay RfiH, contact 83 to terminal C.

Assuming that switches i and IA are reversed, relay R2HX or LGI-IX may be picked up'. Tf relay REHX is picked up and relay LlHX is released, and sections IT and 3T are unoccupied and switch 3 is reversed, relay RBZE will be energized over a circuit from terminal B, contact 82 of relay L4M, contacts l5, 14, contact 84 of Y relay IRKP, contacts 64,55, contact V85 of relay SRKP, contacts 86, 8l, relay RBZH, contact 68 to terminal C. Relay RB2H Will also be energized if switcht is normal and section A4T unoccupied over a circuit similarV to that just traced but in-v cluding contact 88 of relay A4TR instead or contact 85.

It relay LAI-IX is pickedV up and relay RZHXv is released, and switches I, IA and 3 are reversed, Vrelay LCAH will be picked up over the circuit from terminal B, contact 69 of relay H2M, contacts 64, 85|, 74, 15, 8|, relay LC4H, contact 80 to terminal C.

If relay LHX is picked up and relay RZHX is released, and switches ,I and IA are reversed and switch 3 is normal, and if `sections IT and 3T are unoccupied, relay LBlH will be energized over the circuit from terminal B, contact 69 of relay H2M, contacts 64, 84, 14, 75, 16, TI, 89, BQ, relay LBlH, contact 8B to terminal C.

The circuits for the route relays HX which control thesignal relay circuits just traced are shown in Fig. 10. Each route relay HX is a stick relay having a pickup circuit including front contacts of a manually governed signal control relay LHS or RHS, shown in Fig.'11, each pickup circuit including in series the winding of a lock-V as soon as each switch of the route assumes the position to which it has been last operated. Each lockout relay LO when energized opens its back Contact shown in Fig. 1l and included in' the pickup circuit of the signal control relay HS kfor Vthe opposing signal and serves to prevent interference with a signal that has been cleared ifV the operator attempts to clear the opposing signal.

The route network of Fig. l0 also includes normally closed checking contacts 93 and IUI of the time element relays TE of Fig. 6, to insure that these relays are in their normal position when a signal is cleared and will thus be in their proper position to effect a time release of the locking when a signal is put to stop manually.

,Assuming that the switch control relay INWS is energized and switches I and IA are normal, contacts 9d and Illll of relay INKZ will be closed. if relay R2HS is picked'up and relay L2HS is released, relays R21-IX and L2LO will be energized over the circuit from terminal B, contact 9| of relay R2HS, relay RZHX, front contact SZ, contacts 93, 94, back contact 95, relay L2LO to terminal C. If relay L2HS is picked up and relay REHS is released, relays LZHX and R2LO will be picked up over the similar circuit from terminal B, front contact 91 of relay L2HS, relay LHX'contacts 95, 94,93, 92, relay R2LO to terminal C. Assuming further that relay 3KZ is energized, if relay RAHS is picked up and relay Lal-IS is released, relays R41-IX and LllLO will be energized over the circuit from terminal B, front Contact SS of relay RllHS, relay R41-IX, contacts lieto |93, inclusive, relay L4LO to terminal C.`

If relay LGHS is picked Yup and relay R41-IS is released, relays LQHX and HALO will be picked up overV the similar circuit from terminal B, front contact |635 of relay LlIHS, relay LQHX, contacts |93, |92, lill, |00, 99,'relay RIlLO to terminal C.

, Assuming that relays IRKZ and 3KZ are energized, if relay RZHS is picked up and relay L||HS is released, relays RZHX and LGLO will be energized over the circuit from terminal B, front contact 9| of relay RZHS, relay RZHX, contacts 92, 93, |65, IJI, |02, |03, relay L4LO to terminal C. If relay L4HS is picked up and relay RZHS is released, relays LIIHS and RZHS will be ener-V gized over the circuit from terminal B,.fro'nt con-v tact |04 of relay L4HS, relay LIIHX, contacts |03, |02, ll, |05, 93, 92, relayRZLO to terminal Each relay HX, when energized as above described, will complete a vstick circuit including the front contact of the associated signal control relay, but independent of the route network, which serves to hold the relay energized to insure that a signal can not be put to stop inedvertently by the release of a relay KZ due to the contact SI of relay REHS, the Winding-and front contact 9S of relay RZHX, resistor |06 to terminal C. Each resistor such as |06 is proportioned so as to limit vthe-current through the stick circuit to prevent releasing the lockout relay LO which is in shunt with the resistor when the route circuit is closed, but to permit suillcient current to flow to maintain the routerelay HX energized when the routercircut is open. Y

The switch and signal control relays NWS, RWS, LHS and RHS may be controlled in any desired manner, either by direct Wire connection to the contacts of switch and signal levers in a. remotely located control office, or by means of a Vselective communication system of any suitable type, provided, however, apparatus functioning in a manner similar to that herein disclosed, is ineluded between the control levers and the relays to prevent at times the response ofthe relays to lever operations. One type of communication system suitable for controlling the apparatus of my invention is that disclosed and claimed 1n .a United States application Vfor Letters Patent by Lloyd V. Lewis, for Remote control systems, Se-

asf

rial No. 600,786, sied Maren 23, 1932. This sys-Y tem is described in the Book entitledy Centralized Trailic Control System-Time Code Scheme, Manual No. 502, September 1931, published by The Union Switch & Signal Company, Swissvale, Pa.

In Fig. 11, I have shown circuits for ther switch and signal control relays by means of rwhich the manual control of the switches and signals'is effected, as arranged forV control by the delivery relays D and by contacts 9 to I2, inclusive, which contacts are to be understood as beinglcontacts of the selector relays 9 to I2, inclusive, of the time code scheme of the Lewis application. As described in the book referred to, each control code includes station selecting elements for selecting and operating one delivery relay or another momentarily at thefend of the code, and also includes switch control elements which are eiective to selectively close contact 9 or I'I, depending upon whether a switch control lever SW for the switch corresponding to the operated relay Dis in its normal or reverseA position. YIn addition, each control code includes signal control elements which areeiective to selectively close contactIII or I2 if a three-position signal lever Sig. associated with such switch lever has been moved to clearing the signal for the corresponding direction, while contacts Il) and I2 both remain open when the delivery relay D is operated if such signal lever is in its stop position. It is to be understood, therefore, that contacts 9 to I2, inclusive, are operated in accordance with lever position as illustrated diagrammatically by dotted line connections on the drawings, and then relay ID or 3D, as the case may be, is selected and operated momentarily by code. It is evident from the drawings that each pair of switch control relays NWS and RWS is arranged so that one relay or the other :may be picked up by a momentary impulse when the corresponding delivery relay D is energized, provided the selector contact 9 or II, respectively, is closed, the energized relay thereafter being maintained picked up by means of a stick circuit including a back contact of the delivery relay. Each delivery relay D and selector contacts Ill and I2 similarly controls a pair of si nal control relays LHS and RHS, the circuits herein disclosed differing from those described in the book in that the circuits of the signal control relays include contacts of the lockout relays of Fig. 10, which function to prevent interference with a signal that has been cleared by an attempt to energize the signal control relay for the opposing signal.

The relays lVP, shown in Fig. l2, have contacts in the pickup circuits for the switch control relays which serve to prevent at times, the response of the switch control relays to code signals transmitted from the dispatchers oice, but these circuits diifer somewhat from the corresponding circuits of the relays MP described in the book. Referring to Fig. 12, a circuit for relay IMP may be traced from terminal B, contacts IElI, |08, |09, IIS of the approach locking relays M, relay IMP to terminal C. Relay IMP will be deenergized when any one of the signals 2 or 4 is cleared, but will pick up when a train accepts the signal and occupies the corresponding switch section, due to the closing of back contact I of relay 3TZ or back contact I I2 of relay ITZ. The circuit for relay 3MP may be traced from terminal B, contacts lill and IBS of the approach locking relays M ior the upper track, contact ||3 of relay 3S, relay 3MP to terminal C. Relay 3MP will be deenergized when any one of the signals 4 or arm b of signal R2 is cleared but will pick up when a train accepts the signal and enters the corresponding switch section due to the closing of back contact III of relay STZ or back contact I|4 of relay ITZ.

Referring now to Fig. 11, assuming that delivery relay ID picks up momentarily while selector contact 9 is closed and that relays IMP and 3MP Vare energized and also that the dual selector levers IDS and IADS are in the motor position so that contacts IIB and |I9 are closed, a pickup circuit for relay I NWS will be closed from terminal B, contact 9, contact I I5 of relay ID, contacts lI I5 and I I'I of relays I MP and 3MP, relay INWS, contacts IIS and IIS to terminal C. When relay ID releases, a stick circuit for relay INWS is closed from terminal B, back contact |20 of relay ID, back Contact I2I of relay IRWS, front contact IEE and winding of relay INWS, contacts I I8 and IIS to terminal C, to maintain relay INWS energized until relay ID is again operated. If relay ID is operated when the pickup circuit of relay I NWS is open, relay I NWS will become released due to the momentary opening of contact |29. The pickup circuit of relay IRWS may be traced from terminal B, selector contact I I, contacts |23, |24, |25, relay IRWS, contacts II8 and I|9 to terminal C, while its stick circuit which functions in a manner similar to that for relay INWS may be traced from terminal B, contacts |252, |26, |21, relay IRWS, contacts II8 and IIS to terminal C. Each MP contact in the pickup circuit of relays NWS and RWS is shunted by a front contact of the indication relay NKR or RFR. for the corresponding position of the switch in the manner shown in the H. S. Young Patent No. 1,974,439, issued Sept. 25, 1934. If switch indication relay INKP is energized, its contact |28, shunting contacts Il and II'I permits relay INWS to be energized over its pickup circuit including contact 9 when relay ID is operated, even though relay IMP or 3MP is deenergized. Relay ID may thus be freely operated to control the signals 2 for the lower track, or to pick up relay NWS, so long as switches and IA are left normal, but relay INWS will be released without energizing relay IRWS if the operator attempts to reverse the switches before the approaching train passes the signal to initiate the release of the approach locking.

Assuming that delivery relay ID is operated when selector Contact I0 is closed and relay LZLO deenergized, the signal control relay L2HS will become energized over a circuit from terminal B, contacts It?, |29, back contact ISB, relay LZHS to terminal C, and will be held energized after relay ID releases by its stick circuit including contacts IBI, E32, I33 and |34. Relay LZHS may be released manually by operating relay ID while contact IG is open, and will be released automatically by the opening of contact |32 when a train enters section IT, and may then be reenergized while section IT is occupied as soon as relay I'I'Z releases to shunt contact |32 by its back contact |35 to reestablish the stick circuit. Relay R2HS is similarly controlled by contacts |34 and |36 of relay iD, selector contact I2 and contact I3I of relay RZLO.

The switch and signal control relays for switch 3 and signals 4 are controlled by a delivery relay 3D and are shown at the right in Fig. ll, the circuits for these relays being similar to those already described as will be apparent from the drawings.

Considering now the lockout relays LO, if the crossover is reversed and relay L4HS has been picked up and signal LC4 or arm b of signal L4 has been cleared, it is apparent from Fig. 10 that relay RZLO will be energized, and if relay VID is then operated for the purpose of clearing the opposing signal R2, the energization of relay RZHS is prevented because back contact |31 of relay RELO in the pickup circuit of relay RZHS is open, and consequently, the closing of a connection from terminal B to the network circuit or" Fig. l0 to interfere with the energization of relay LQHX is prevented. Similar conditions prevail if the signal for the opposite direction over the same route is cleared, in which case relays RIZHS and L4LO will be energized and the energization of relay LIIHS will be prevented. If, now, the crossover is normal and relay LZ1-IS has been picked up and signal L2 cleared, relay R2LO will be picked up to open its back contact I 37 in the pickup circuit of relay RZHS. Since relay RZHS is controlled by the same relay, namely, relay ID, as relay L2HS, the operation of relay ID with selector contact I2 closed, will open Contact I3| in the stick circuit of relay LZHS, but a circuit is now closed which may be traced from terminal B, contacts I2, |36, front contact Isl or relay RzLo, contacts Isaias, |34', relay LZ1-IS, to terminal C, so that relay LZHSis pre-n Y Vented from releasing due to an attempt to pickYV up relay RZHS. Relay LZHS may, of course, be released tof put signal manually to stop by operating relay ID to open contact ISI when contacts I and I2' are both; open. Each ci the remaining relays in Fig. 1l are controlled Vin a similar manner, as willgbe apparent from the drawings. VWith all of the apparatus in the normal condition as shownV in@V the drawings, Vit will beevident that the operator is freeVV toy reverse'the switches andto clear anyl of the signals. Torexplain the operation of the system, however, I will rst assume that the switches are left normal andl the `openator transmits a code to clear arm c ofi,Y

usignal topermitv a train to move from leftY tor right tlover the lower Vmain track. The eilectY of the cede willbe to closecontacts 9 and I2gV and to piek up relay ID momentarily, relay INWSr relay RZM of Fig. 6, which releases in turn toY Y lock Yswitches I and `IA normal ,by the opening 9 is open resultamerelyin releasing relay IN WSSV oi'cofntact 29 in the circuit for relays I WR and release relay IlVIP of Figi. l2,

Referring Y'to Fig. 11, it will be noted that the operator is now prevented from electing any control by the operatiorr of relay ID other than to return the cleared signal to stop. Thus an attempt to reverse switches I and IA by operating relay ID when contact I I is closed andV contact IAWR of Fig. 4', and also opens Contact |09 tof without energizing relay IRWS, because contact |24 of relayIMP in the pickup circuit for relay IRWS is open., An attempt to clear thef opposing signal L2 by operating relay ID when contactl is clcsedand contact I2 open is without elect, relay LZHS being prevented from: pickingup because back contact I3() of relay; L2LO in its pickup circuit is open, while relaye R2HS is prevented from releasing because when contact I3I of relay ID is open it is bridged by a circuit including front contacts I0, I29'and 1I3l). It istobe noted however,V that sincethis circuit includes contact I 9, contact I 3| will beeiective to'release relay VR2HS in the event the operator Vsends a signal stop code operating relay ID when contacts Ill and I2 are both open.

Arm a of Vsignal R2 having been cleared, the voperator may now operate switch 3 or clear any one of the signals governing the movement of tranic over the upper track with switch IAnormal. To clear arma oi signal L4, for example,

h he will transmit a code to close contacts 9 and I0 Vopens `its contact |98, shown in Fig. l2, tol deenergize relay 3MP. The operator now has nclv controleover the apparatus controlled by relay 3D other than to deenergizerelay LAI-IS to put the signal toystop, `because, contact I 39 of relay 3MP in the pickup circuit ci relay BRWS is open, and back centact I 4t in the' pickup circuit of relay R41-LS is open.

I will now assume R2 with arm ai at clear, enters section IT. Relay ITR will release, opening contact 22 in the circuit of relays IWR'Yand IAWR, opening contact 65 to release relay RAEH, opening contact I32'to kre'- lease relay REIIS, opening contact' to release relay I'FZ, andopening Contact 59, showninFige, toV prevent theiinitiation oi an operation of relay ETE when relay RA2II releases toI close Contact 36. Relay RAZH upongreleasing alsok closes back contact ISI to light lamp R 'to cause signal R2 to indicate stop. Relay R21-IS uponn releasing opens its stick contact I4Iand also cpens` contacts 9| and 92, in theroute network to Erelease relay R21-IX, which relay in turn o-pens contacts (Sil and 68, in the signal network toy release relay RAZI-I, so that the signal willremain atestop afterV the train leaves section IT and until it is again manually governed. Relay ITZ upon releasing opens its contact 23 in thecircuit of relays IWR and IAWR, and closes its backicontact I I2 in the Vcircuit of relay IMP, but this relay will not pick thatfa train accepting signal section IT enters section 2T, relay 2TR will rexlease, completing the pickup circuit for relay RZM including back contacts 52 and 54 so that relay REM will pickup. Relay Z'IRalso opens contact 65, shown in Fig. 9, in the circuit for relay RAZH, so that Vif relay R21-IS is again'energized thesignal will not clear until the train vacates section 2T. Y Y

If, now, a second train accepts signal Land enters section 3T,'relays LHSand 3TZ willbecomefdeenergized to initiate a sequence of operations similar to those just described, andas scp-n as relay 3TZ releases theY closing of its: back contact III will cause relays IMP and 3MP to pick up. Since relay LZLO is released, the Yswitchand signal control relays governed by relay ID are fully restored to the control of the'loperator. It follows that as soon as a train passes a'signal and a relay TZk releases, relays LEHS and RZHS are rendered responsive to codes for clearing the sigto clear the same signal or a different signal governed by the same relays and the code will be stored by one of these relays until conditions are favorable for clearing the signal. Furthermore, since the switch control relays INWS and IRWS are also rendered responsive to codes, it will be apparent that the operator may at the same time send a nell. code to operate the switch provided either the Vapproach locking associated with other signals governing traino over the same switch is released or the corresponding track sec'- tions are Occnpied. This switch operating code will then be stored by one of the switch control relays, and just as soon as conditionsV become favorable for the'operation cf the switch sothat the switch locking becomes fully released, the switch will operate automatically without further attention upon the part of the operator. Y

I will next assume that with section 3T occu? pied, the operator transmits a code in which relay 3D is operated while contacts II :and I9 are closed, so as to pick up relays' SRWSfand MHS 75 for the purpose of reversing switch 3 and of clearing signal LC4 for a train movement from the siding through sections 3T and 4T. When relay 3D picks up, however, the first result will be to release relay SNWS which will open contact 38, shown in Fig. 5, to quickly release relay 3K2, which relay in turn will open contact m2 in the route network so that when front contacts |211 Vand M33 of relay R41-IS close, relay RAHX will not pick up. When the train in section 3T enters section 4T, the pickup circuit for relay L4M will become closed over contacts |38, |62 and |43, so that relay L4M Will pick up to close contact |58 in the circuit of relay 3WR. Relay SWR will become energized in the reverse direction over the circuit including front contact 2 'I of relay @RWS and back contact 26 of relay 3NWS as soon as the train passes entirely out of section 3T and relays STR and STZ pick up toV close contacts |44 and lli-5. Relay SWR will then reverse its contacts to energize the switch motor of the switch machine SSM to reverse the switch, and when switch 3 completes its movement to reverse, relay SKR will become energized in the reverse direction" and relays SKRP and SKZ will pick up, relay BKZ closing contact |92 so that relays LfHX and RALO will pick up in series. Relay LllHX will now close contacts l5 and 88 in the signal network, and contact 8| of relay 3RKP also being closed, relay LCeH will pick up, clearing signal LC, and by opening its back contact |45 releasing relay Lili to open contacts and |5| to lock the switches, relay L4M also opening contact |8 to release relays |MP and 3MP. It will be apparent from Fig. 8 that since the switches are normal, the normal switch indication relays lNKP and SNKP are energized, and that contacts t28 and |52 of these relays shown in Fig. l0, are closed, so that the normal switch control relays lN'WS and @NWS remain responsive to codes. The contacts of the reverse indication relays lRKP and SRKP will be open, however, and since contact |24 of relay IMP and contacts |25 and |39 of relay 3MP are also open, relays IRWS and SRWS are nonresponsive to codes.

I will now assume that the operator forgets that signal LCd is at clear and attempts to clear arm b of signal R2 by operating relay |D with selector contacts and l2 closed. When relay |D picks up, contact |29 opens to release relay lNWS, and relay INKZ releases to open contact 94 in the route network. Contact |65 of relay ERKZ being also open, it follows that relay RZHX will not become energized when relay R21-IS picks up. Relaw IRWS will not pick up when relay l D is operated becouse relay IMP is deenergized.

In this instance, it will be evident that if the signal network circuits of Fig. 9 were controlled directly by the signal control relays, switch being locked normal, the energization of relay REHS would have cleared arm a of signal R2, and the train would have been directed into a route different from the intended route. This can not happen when the signals are controlled as herein disclosed because the route relays HX interposed between the signal control relays and the signals become energized only when each switch of a route and its switch control means are in corresponding positions.

Furthermore, in the case just described, when relay INKZ releases to prevent the improper clearing of arm a of signal R2, its contact |00 in the route circuit previously closed to clear signal LC4 also opens, but relay LllHX will then be held energized over its stick circuit including Contact |47' and resistor |48 so that signal LC4 will not be interfered with.

It is to be understood that the usual indication lamps are provided in the dispatchers cice to indicate the condition oi the relays KR and of the signal relays H, so that when a switch or sig nal fails to respond to its manual control the operator will be informed of the fact. In the case described, as soon as the operator nds that signal R2 can not be cleared, he will restore the apparatus to its former condition by transmitting a code to pick up relay |NWS, this being possible because contact |28 oi relay |NKP in the pickup circuit of relay lNWS is closed.

I will neXt assume that the operator transmits a code in which relay 3D is operated when contacts I0 and I2 are both open, in order to release relay LI-IS to put signal LC-l to stop. When relay 3D is operated, relay LGI-IS will release, releasing relay LI-IX, and then relay LClH will release to close its back contact |46, shown in Fig. 6, thereby energizing the time element relay TE to pick up relay L4M at the end of a predetermined time interval. Since relay LlM has a front contact 82 in the signal network of Fig. 9 in the circuit of relay RllH, and front contacts il and |5| in the circuits of relays WR, it is clear that the immediate clearing of the opposing signal Rf: or the immediate reversal of switches and IA or of switch 3 will be prevented when signal L04 is put to stop manually.

I will now assume that the apparatus is in the normal condition as shown in the drawings, and that the relays i D and 3D are both operated to reverse both the crossover and switch 3 to clear arm b of signal R2 for a train movement from left to right from section AZT to the siding. In this instance, relay ID will be operated when contacts and I2 are closed and rela-y 3D will be operated when only contact I l is closed. When relay ID operates, relay INWS will release and relays lRWS and R2HS will pick up and when relay 3D operates, relay BNWS will release and relay SRWS will pick up. Relays INKZ and BKZ will thus be released by the opening of contacts 38 and 42, as shown in Fig. 5, and since all of the approach locking relays are energized and the switch sections are unoccupied, the switches will be unlocked so that relays EWR, IAWR and SWR will be operated to reverse, energizing the switch motors in the reverse direction to move the switches to reverse. Contact 110 of relay BRWS shown in Fig. 5 being closed, relay SKZ will then be reenergized because when switch 3 reverses relay SRKP becomes energized to close contact 4|, and relay IRKZ will like- Wise become energized when the crossover reverses. Contacts 9| and 92 of relay R2HS being closed, relay RZHX will become energized as soon as contacts |52 and |05 of relays BKZ and lRKZ close, that is to say, as soon as each switch of the route has been operated tothe position corresponding to that of its switch control means, and relay LLlLO will become energize-d in series with relay RZHX. When relay REHX picks up, its contacts 64 and 68 in the signal network, Fig. 9, will close, and since contacts 34 and of relay |RKP are closed and the corresponding contacts G3 and 6'! of relay |NKP are open, relay RBZI-I will become energized to clear arm b of signal R2. Since relay LLO is energized in series with relay RZHX, the operator will be unable to energize relay L4HS if he attempts to clear the opposing signal LCG, and operates relay 3D when contact I0 is closed, because back contact |49 of relay LliLO in the pickup circuit Y of relay LflHS will be open. Furthermore, any

operation of relays lD and 3D for the purpose of restoring any of the switches to normal to set up other conflicting routes will result merely in the Ideenergization of the switch control relays RWS and the opening of the contacts of the Yrelays KZ in the route network, t is however being without effect upon the signal which has been cleared becauseV relay R21-IX will be retained energized over` its stick circuit including contact 96. It is also clear that the operator willbe unable to clear any con'icting signal because he will be unable to pick up any other HX relay.

In the case just described, when relay RB2I-I Y picks up contact 4l will open to release relay REM.

Relay REM upon releasing locks the crossover Y reversed by opening contact 2t in the circuit for relays lWR and EAWR, and also opens contact Vl'to release the section locking relay 3S, shown in lig` 7, and opens contact m9 to release relay HMP. Relay 3S, upon releasing, locks switch 3 reversed by opening contact lll'in the circuit for relay SWR and also-opens contact l I3 to release relay 3MP. When the train accepting signal R2 enters section iT and relay lTZ releases,V its back contacts H2 and lid close and relays 3MP kand IMP are reenergized to condition the switch control relays to receive any codes that the operator may transmit to set up a new route. The switches being locked, this Ycode will be sto-red. Relay REM will pick up when thetrain enters section 3T'and relay STZ closes its back contact 55. Relay 3S willpickup kwhen the train passesout of section iT and relay Vi'ITR closes its front contact S, and the switch locking will be released to permit the relays WR to be operated just as soon as thertrain passes out of section 3T and relay BTZ closes its front contacts 24 and H35.

- Assuming next that signal L04 is cleared for a` movement in the opposite direction over the same route as in the preceding example, it will be noted that the switches will be locked by relay LiM instead of by relays RM and 3S, and that the locking of switch 3 will be released as soon as Y the train, moving toward the left, passes out of section 3T, while switches l and iA will be locked reverse until the train passes out of section IT.

In illustrating my invention I have assumed that each switch or crossover and the associated pair of opposing signals will be controlled by the same code and by a single relay D. It is obvious, however, that individual codes or direct wire control may be employed interchangeably, and that relays INWS and IRWS may for example be controlled by one relay D and relays LZHS and RZHS by another relay D. This is because the arrangement of the apparatus of my invention is such that these relays D may beoperated at any time whatsoever and the control relays will respond to their manual control only when conditions are favorable for their operation, with the single exception that codes may be stored after a train enters a switch section to become effective after it vacates the switch section. Furthermore, by reason of this storing of codes, my

` Vsystem provides for the prompt operation of the switches and signals under congested trame conlayout, it will be clear that the sameprinciples 'can be applied to complicated layouts involvingr large numbers of traiiic routes 4and that the sys'- tem of my invention provides relatively simple and reliable apparatus for safely controlling in-` terlocked railway track switches and signals from la remotely located ofce or cabin, in such a manner that a train can not be run over a route different from the intended route due to failure of a switch to respond to an operation of its control means and likewise that my system is so arranged as to provide a maximum degree of protection against interference with the movement of traic when a signal has been cleared for an approaching train.

Although I have herein shown and described only one form of railway traffic controlling ap- Vparatus embodying my invention, it is -under' Vcontrolling the operation of each switch of the route, a signal control relay and a route relay for each signal', 'a pickup circuit for each route relay closed when the associated signal control relay is energized provided each switch of the route agrees as to position with its switch con-V trol means and the signal control relay for the opposing signal is deenergized, a stick circuit'for each route relay controlled by the associatedY signal control relay only, anda circuit for clearing each signal controlled by each switch of the route and closed only when the associated route relay is energized and the route relay for the opposing signal is deenergized. Y

-2.,In combination, a trafc route including a plurality ofrailway track switches, a signal at each end of the route to govern the movement of n traffic in opposite directions over the route, manually controllable switchcontrol means for controlling the operation of each switch of the route,

a signal control relay and a route relay for each Y signal, an energizing circuit for each route relay closed only when the associated control relay is energized provided each switch of the route agrees as to position with its control means and the control relay for the opposing signal is deenergized, means preventing the release of each route K relay when the associated control relay is energized if said energizing circuit is opened by the operationY of the switch :control means for a switch of said route, a circuit for clearing each signal controlled by each switch of therouteand closed only when the corresponding route relay is energized,V and means preventing the operationY Y of any'switch of said route in VVresponse to the operation ofY itsy control Vmeans when one of said signals has been cleared. Y

3. In combination, a traflic route including a plurality of railway track switches, two opposing signals including one at each end of the rroute to govern the movement of traffic in opposite directions over the route, manually controllable switch control means for controlling the operation of each switch of the route, a manually con;A

trollable signal control relay and a route relay for each signali Va pickup circuit for each route relay closed when the associated signal control relay is energized and the opposing signal'con'- trol relay is deenergized provided each switch of the route agrees as to position with its switch control means, a stick circuit for each route relay controlled by the associated signal control relay only, and a circuit for clearing each signal closed when the associated route relay is energized and the opposing stick relay is deenergized provided the switches are positioned to establish said route and the opposing signal is deenergized.

4. In combination, a trafiic route including a plurality of railway track switches, switch control means for each switch of the route, a manually controllable signal control relay, a route relay, a pickup circuit for said route relay closed only when the signal control relay is energized and each switch of the route agrees as to position with its control means, a stick circuit for said route relay closed when said route relay is picked up and the signal control relay is energized, a signal for governing the movement of traffic over said route, and a circuit for clearing the signal closed only when said route relay is energized.

5. In combination, a trailic route including a plurality of railway track switches, switch control means for each switch of the route, a manually controllable signal control relay, a route relay, a pickup circuit for said route relay closed only when the signal control relay is energized and each switch of the route agrees as to position with its control means, a stick circuit for said route relay closed when said route relay is picked up and the signal control relay is energized, a signal for governing the movement of trafc over said route, an operating circuit for each switch of the route controlled by the corresponding switch control means and closed only when said signal is in its most restrictive condition and a circuit for clearing the signal closed only when said route relay is energized.

6. In combination, a traffic route including a plurality of railway track switches, manually controllable switch control means for each switch of the route, a manually controllable signal control relay, a route relay controlled by said signal control relay, means effective when the manually controllable switch control means for each switch of the route has been operated and said signal control relay has been energized for preventing the energization of said route relay until each switch of the route assumes a position corresponding to that of its switch control means, a signal for governing the movement of traffic over said route, and means controlled by said route relay and by each switch of the route for controlling said signal independently of the condition of said switch control means.

'7. In combination, a traffic route including a railway track switch, a signal at each end of the route to govern the movement of traffic in opposite directions over the route, manually controllable switch control means for controlling the operation of the switch, a manually controllable signal control relay for each signal, a route relay and a lockout relay for each signal control relay, a circuit for energizing each route relay and the corresponding lockout relay in series including a front contact of the associated signal control relay and a back Contact of the signal control relay for the opposing signal, said circuit also including contacts closed only when the switch and its control means are in corresponding positions, a circuit for clearing each signal closed when the corresponding route relay is energized, and means controlled by each lockout relay eiective to prevent the signal control relay for the opposing signal from becoming energized when such lockout relay is energized.

8. In combination, a tramo route including a railway track switch, two opposing signals including one at each end of the route to govern the movement of traiiic in opposite directions over the route, manually controllable switch control means for controlling the operation of the switch, a manually controllable signal control relay and a route relay for each signal, a pickup circuit for each route relay closed only when the associated signal control relay is energized and the opposing signal control relay is deenergized provided the track switch agrees as to position with its control means, a stick circuit for each route relay controlled by the associated signal control relay only, means rendered eiective when either of said route relays is energized to prevent the energization of the signal control relay for the opposing signal, and a circuit for clearing each signal closed only when the associated route relay is energized.

9. In an interlocking system for railroads, a traic route including a plurality of railway track switches, a signal to govern the movement of trairlc over said route, a route relay for controlling said signal, a remote controlled switch control relay for each switch, means controlled by each switch controlled relay for controlling the corresponding switch, a remote controlled signal control relay, a pickup circuit for said route relay controlled by said signal control relay and by the switch control relay for each switch of the route, a stick circuit for said route relay controlled by said signal control relay only, and a circuit for clearing said signal controlled by each switch of the route and closed only when said switches are in position to establish said route and said route relay is energized.

10. In combination with a railway track switch, a route network comprising a iirst conductor having one end connected to the adjacent end of a second conductor when the switch is normal and to the adjacent end of a third conductorwhen the switch is reversed, a signal for governing the movement of traiiic over said switch associated with each conductor, a control relay for each signal, a plurality of lockout relays including one for each conductor each connected to the free end of such conductor over a back contact of the associated control relay and to one terminal of a source of current, a plurality of route relays including one for each conductor each connected to the free end of such conductor and to the other terminal of said source over front contacts of the associated control relay, a manually governed circuit for each control relay including a back contact of the associated lockout relay, and a control circuit for each signal including a iront contact of the associated route relay.

11. In combination with a railway track switch, two signals, one for each position of the switch, for governing the movement of traiic over the switch, signal control means including selecting means for selecting one signal or the other for clearing in accordance with the position of the track switch and also including a relay for clearing the selected signal, remote control means for operating said selecting means and said relay, a locking relay which becomes deenergized when either signal is cleared and which remains deenergized when such signal is manually put to stop provided there is a train approaching within a through said layout, a control relay and a lock-out relay for each signal, a pick-up circuit for each control relay including a code-controlled contact and a back contact of the associated lock-out relay, a stick circuit for each control relay including a normally closed code-controlled contact, a route relay for each signal for controlling such signal, and an energizing circuit for each route relay controlled by the corresponding control relay in accordance with the positions of said track switches and closed only when the route governed by the signal which such route relay controls has been established, said energizing circuit also including the Winding of the lock-out relay for the signal for the opposite direction for the same route.

20. In a centralized traice control system for railroads, a track layout comprising two parallel tracks connected by a crossover, a plurality of signals including one for each direction for each track for governing the movement of traic over dilerent routes through said layout, switch controlmeansfor operating the switches of said crossover, a signal control relay for each signal, a route relay for each signal for controlling such signal, a pickup circuit for each route relay controlled by the corresponding control relay and by said switch control means and closed only when the switches and the switch control means occupy corresponding positions and the position of the switches is such as to establish the route governed by the signal which such route relay controls, a stick circuit for each route relay controlled by the corresponding control relay only, and means ren-y dered effective when a route relay is energized to prevent the clearing of the opposing signal for the same route.

EARL M. ALLEN.

DISCLAIMER 2,046,049-Earl M. Allen, Swssvale, Pa. RAILWAY TRAFFIC CONTROLLING PPARATUS. Patent dated June 30, 1936.

Disclaimer filed March 21, 1939, by the assignee, The Union Switch de Signal ompany.

Hereby disclaims the subject matter of claims 1, 3, 9, and 20 in said patent.

[Qcial Gazelle April 18, 1939.] 

